A makeover voucher is received by males upon completion of the Recruitment Drive quest. They can use it to change their gender with the makeover mage near Falador. The quest will still reward a voucher, but changing your gender is now free, making this a rather useless item.

This is given as a reward to male players because they have to change their gender during the quest. However, you will not receive a voucher if you change gender before doing the quest.